1 /*- 2 * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #ifndef _FENV_H_ 30 #define _FENV_H_ 31 32 #include <sys/_types.h> 33 34 #ifndef __fenv_static 35 #define __fenv_static static 36 #endif 37 38 typedef __uint64_t fenv_t; 39 typedef __uint64_t fexcept_t; 40 41 /* Exception flags */ 42 #define FE_INVALID 0x00000001 43 #define FE_DIVBYZERO 0x00000002 44 #define FE_OVERFLOW 0x00000004 45 #define FE_UNDERFLOW 0x00000008 46 #define FE_INEXACT 0x00000010 47 #define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_INEXACT | \ 48 FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) 49 50 /* 51 * Rounding modes 52 * 53 * We can't just use the hardware bit values here, because that would 54 * make FE_UPWARD and FE_DOWNWARD negative, which is not allowed. 55 */ 56 #define FE_TONEAREST 0x0 57 #define FE_UPWARD 0x1 58 #define FE_DOWNWARD 0x2 59 #define FE_TOWARDZERO 0x3 60 #define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ 61 FE_UPWARD | FE_TOWARDZERO) 62 #define _ROUND_SHIFT 22 63 64 __BEGIN_DECLS 65 66 /* Default floating-point environment */ 67 extern const fenv_t __fe_dfl_env; 68 #define FE_DFL_ENV (&__fe_dfl_env) 69 70 /* We need to be able to map status flag positions to mask flag positions */ 71 #define _FPUSW_SHIFT 8 72 #define _ENABLE_MASK (FE_ALL_EXCEPT << _FPUSW_SHIFT) 73 74 #define __mrs_fpcr(__r) __asm __volatile("mrs %0, fpcr" : : "r" (__r)) 75 #define __msr_fpcr(__r) __asm __volatile("msr fpcr, %0" : "=r" (*(__r))) 76 77 #define __mrs_fpsr(__r) __asm __volatile("mrs %0, fpsr" : : "r" (__r)) 78 #define __msr_fpsr(__r) __asm __volatile("msr fpsr, %0" : "=r" (*(__r))) 79 80 __fenv_static __inline int 81 feclearexcept(int __excepts) 82 { 83 fexcept_t __r; 84 85 __mrs_fpsr(&__r); 86 __r &= ~__excepts; 87 __msr_fpsr(__r); 88 return (0); 89 } 90 91 __fenv_static inline int 92 fegetexceptflag(fexcept_t *__flagp, int __excepts) 93 { 94 fexcept_t __r; 95 96 __mrs_fpsr(&__r); 97 *__flagp = __r & __excepts; 98 return (0); 99 } 100 101 __fenv_static inline int 102 fesetexceptflag(const fexcept_t *__flagp, int __excepts) 103 { 104 fexcept_t __r; 105 106 __mrs_fpsr(&__r); 107 __r &= ~__excepts; 108 __r |= *__flagp & __excepts; 109 __msr_fpsr(__r); 110 return (0); 111 } 112 113 __fenv_static inline int 114 feraiseexcept(int __excepts) 115 { 116 fexcept_t __r; 117 118 __mrs_fpsr(&__r); 119 __r |= __excepts; 120 __msr_fpsr(__r); 121 return (0); 122 } 123 124 __fenv_static inline int 125 fetestexcept(int __excepts) 126 { 127 fexcept_t __r; 128 129 __mrs_fpsr(&__r); 130 return (__r & __excepts); 131 } 132 133 __fenv_static inline int 134 fegetround(void) 135 { 136 fenv_t __r; 137 138 __mrs_fpcr(&__r); 139 return ((__r >> _ROUND_SHIFT) & _ROUND_MASK); 140 } 141 142 __fenv_static inline int 143 fesetround(int __round) 144 { 145 fenv_t __r; 146 147 if (__round & ~_ROUND_MASK) 148 return (-1); 149 __mrs_fpcr(&__r); 150 __r &= ~(_ROUND_MASK << _ROUND_SHIFT); 151 __r |= __round << _ROUND_SHIFT; 152 __msr_fpcr(__r); 153 return (0); 154 } 155 156 __fenv_static inline int 157 fegetenv(fenv_t *__envp) 158 { 159 160 __mrs_fpcr(&__r); 161 *__envp = __r & _ENABLE_MASK; 162 163 __mrs_fpsr(&__r); 164 *__envp |= __r & (FE_ALL_EXCEPT | (_ROUND_MASK << _ROUND_SHIFT)); 165 166 return (0); 167 } 168 169 __fenv_static inline int 170 feholdexcept(fenv_t *__envp) 171 { 172 fenv_t __r; 173 174 __mrs_fpcr(&__r); 175 *__envp = __r & _ENABLE_MASK; 176 __r &= ~(_ENABLE_MASK); 177 __msr_fpcr(__r); 178 179 __mrs_fpsr(&__r); 180 *__envp |= __r & (FE_ALL_EXCEPT | (_ROUND_MASK << _ROUND_SHIFT)); 181 r &= ~(_ENABLE_MASK); 182 __msr_fpsr(__r); 183 return (0); 184 } 185 186 __fenv_static inline int 187 fesetenv(const fenv_t *__envp) 188 { 189 190 __msr_fpcr((*__envp) & _ENABLE_MASK); 191 __msr_fpsr((*__envp) & (FE_ALL_EXCEPT | (_ROUND_MASK << _ROUND_SHIFT)); 192 return (0); 193 } 194 195 __fenv_static inline int 196 feupdateenv(const fenv_t *__envp) 197 { 198 fexcept_t __r; 199 200 __mrs_fpsr(&__r); 201 fesetenv(__envp); 202 feraiseexcept(__r & FE_ALL_EXCEPT); 203 return (0); 204 } 205 206 #if __BSD_VISIBLE 207 208 /* We currently provide no external definitions of the functions below. */ 209 210 static inline int 211 feenableexcept(int __mask) 212 { 213 fenv_t __old_r, __new_r; 214 215 __mrs_fpcr(&__old_r); 216 __new_r = __old_r | ((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); 217 __msr_fpcr(__new_r); 218 return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); 219 } 220 221 static inline int 222 fedisableexcept(int __mask) 223 { 224 fenv_t __old_r, __new_r; 225 226 __mrs_fpcr(&__old_r); 227 __new_r = __old_r & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); 228 __msr_fpcr(__new_r); 229 return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); 230 } 231 232 static inline int 233 fegetexcept(void) 234 { 235 fenv_t __r; 236 237 __mrs_fpcr(&__r); 238 return ((__r & _ENABLE_MASK) >> _FPUSW_SHIFT); 239 } 240 241 #endif /* __BSD_VISIBLE */ 242 243 __END_DECLS 244 245 #endif /* !_FENV_H_ */ 246